Universal anchor for attaching objects to bone tissue

ABSTRACT

An anchoring device and method for attaching an object to a bone comprises an anchoring member having proximal and distal ends, with the proximal end being adapted to hold the object to the bone while the distal end is in the bone, and a locking member having proximal and distal ends, with the proximal end adapted to secure the anchoring member into the bone and oppose its pull-out or loosening by stopping its backing or preventing its unscrewing while the distal end is in the bone. Also provided are first and second fasteners, with the first fastener adapted to fit to the proximal end of the anchoring member, and the second fastener adapted to fit to the proximal end of the locking member. The end of the second fastener can have an angle that matches an angle of the locking member.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of U.S. application Ser. No.12/934,196, filed Sep. 23, 2010, which is national phase applicationunder 35 U.C.S. § 371 of PCT Application No. PCT/US09/38376, filed Mar.26, 2009, which claims priority to and the benefit of U.S. ProvisionalApplication Ser. No. 61/039,464, filed Mar. 26, 2008, the entiredisclosures of which are incorporated by reference into thisapplication.

FIELD OF THE INVENTION

The present invention relates to devices for attaching various objects,such as prostheses or implants, to bones, and in certain cases foranchoring spinal instruments to the vertebrae of the human rachis.

BACKGROUND OF THE INVENTION

The fast-growing aging population represents an important orthopedicmarket with a very specific need related to its low-quality cancelous orspongy bone (osteoporosis). Osteosynthesis procedures in such people arejeopardized by the risk of loosening in relation with the pullout orback-out of anchors in the bone. The reliability of an anchoring systemdepends on its ability to resist pulling out of the bone. Removal of ananchor may lead to extrusion, or even worse, loosening of any objectattached to the bone. Known anchoring systems propose several solutions:Divergent or convergent screws have been proposed to oppose to pull outforces by increasing the grip. Locking mechanisms intended to secure theanchor within the object (such as locking screw or anti-reverse systems)avoid the pull out of the anchor but not the extrusion of the entireconstruct. Bicortical screwing may be dangerous and can make theconstruct too rigid. This can lead to the breakage of the implantitself. Special features like conical core, self-tapping profile androughened surfaces of the anchor have been developed to increase thegrip to the cancelous bone. Expandable mechanisms (such as threaded pegexpanded with a coaxial inner member or “Molly screw”) crush and splitfragile bone tissue and then creates an empty room around the buriedpart of the anchor. This can lead the construct to toggle and thereforeto a condition for pull out or loosening in response to physiologicalmicro-motions.

U.S. Pat. No. 6,695,844 to Bramlet et al discloses an expandable-wingedfastener made up of an outer member and an inner mechanism able toprotract or retract wings intended not only to increase the interfacebetween the bone and the device but also to expand within the cancelousbone. Although the wings are blunted, the bone-implant interface isweakened as the wings expand or retract because the expanded wingsbroach through the bone as they pivot and therefore require the bone toremodel.

Other solutions use an interlocking mechanism, such as a K-wire whichintersect a bone screw (“An Interlocking Screw for Fixation inOsteoporotic Bone” described by McKoy and al. in “internal fixation inosteoporotic bone” authored by Yuehuei H. An in 2002) or two membersconnected by their ends through a threaded connection (“Anchoring Systemfor Fixing Object to bones” U.S. patent application Ser. No. 10/275,710to Lionel Sevrain).

Connecting solutions address some of the problems, and provide increasedstrength and reliability, but require an aiming system that mayrepresent a hurdle not only from a marketing standpoint but also from ananatomical standpoint. There is therefore a need for an improvedanchoring system and installation method for anchoring an object tobone.

It would be desirable to provide a novel anchoring system for securingvarious objects to bones, such as spinal devices or instrumentations tothe rachis, and to provide an anchoring system well adapted to prevent apull out of the anchor and therefore the extrusion and/or the looseningof the object over time. It would also be desirable to provide ananchoring system to bring the needed reliability in such osteoporoticbone, without the hassle of an additional aiming guide.

SUMMARY OF THE INVENTION

Therefore, in accordance with a first aspect, there is provided ananchoring device for attaching an object to a bone, comprising ananchoring member having proximal and distal ends, the proximal end beingadapted to hold the object to the bone while the distal end is in thebone, and a locking member having proximal and distal ends, with theproximal end adapted to secure the anchoring member into the bone andoppose its pull-out or loosening by stopping its backing or preventingits unscrewing, while the distal end is in the bone.

Also in accordance with another aspect, there is provided first andsecond fasteners, the first fastener being adapted to fit to theproximal end of the anchoring member, and the second fastener beingadapted to fit to the proximal end of the locking member. Morespecifically, the second fastener is adequately designed to match theangulation of the locking member.

Further in accordance with another aspect, there is provided a methodfor mounting an object to a bone, comprising the steps of: (a) providinganchoring member and locking member each having proximal and distalends, (b) introducing the anchoring member in the bone wherein saidproximal end holds an object to the bone, (c) positioning the lockingmember into the proximal end of the anchoring member, and (d) preventingthe anchoring member of loosening.

In one embodiment of the invention, there is a system for attaching oneor more objects to bone tissue, comprising: an anchoring member havingproximal and distal ends, wherein the proximal end comprises a socketand an aperture, wherein the aperture is oblique to the axis of thelength of the anchoring member; and a locking member having proximal anddistal ends, wherein the proximal end comprises a socket; wherein theaperture of the anchoring member is adapted for insertion of the lockingmember therethrough. In a specific embodiment, the system furthercomprises at least one fastener, wherein the fastener is adapted to fitto a socket in the proximal end of the anchoring member, adapted to fitto a socket in the proximal end of the locking member, or both. In onespecific embodiment, the system further comprises first and secondfasteners, wherein the first fastener is adapted to fit to a socket inthe proximal end of the anchoring member and the second fastener isadapted to fit to a socket in the proximal end of the locking member.

In another embodiment of the invention, the angle on the head of thesecond fastener corresponds to the angulation of the locking memberinserted into the anchoring member. In other specific embodiments, theanchoring member, the locking member, or both have a rough surface. Incertain aspects, the surface of the inner wall of the aperture issmooth, rough, or threaded. In particular aspects of the invention, theangle between the axis of the length of the anchoring member and theaxis of the length of the locking member is between 1 and 89 degrees,between 10 and 75 degrees, between 10 and 50 degrees, between 10 and 35degrees, or between 25 and 30 degrees.

In a specific embodiment of the invention, the shape of the socket ofthe anchoring member and/or the shape of the socket of the lockingmember is hexagonal, pentagonal, square, triangular, cross-shaped, plussign-shaped, linear, or star-shaped. In a particular aspects of theinvention, the second fastener is a ball end hexagonal fastener.

In one embodiment of the invention, there is a method of affixing one ormore objects to bone, comprising the step of anchoring the object to thebone using the system(s) or composition(s) of the invention. In anotherembodiment of the invention, there is a kit comprising the system(s) orcomposition(s) of the invention.

The foregoing has outlined rather broadly the features and technicaladvantages of the present invention in order that the detaileddescription of the invention that follows may be better understood.Additional features and advantages of the invention will be describedhereinafter which form the subject of the claims of the invention. Itshould be appreciated by those skilled in the art that the conceptionand specific embodiment disclosed may be readily utilized as a basis formodifying or designing other structures for carrying out the samepurposes of the present invention. It should also be realized by thoseskilled in the art that such equivalent constructions do not depart fromthe spirit and scope of the invention as set forth in the appendedclaims. The novel features which are believed to be characteristic ofthe invention, both as to its organization and method of operation,together with further objects and advantages will be better understoodfrom the following description when considered in connection with theaccompanying figures. It is to be expressly understood, however, thateach of the figures is provided for the purpose of illustration anddescription only and is not intended as a definition of the limits ofthe present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Having thus generally described the nature of the invention, referencewill now be made to the accompanying drawings, showing by way ofillustration a particular embodiment thereof.

FIG. 1 is a schematic perspective view of an anchoring member inaccordance with the present invention.

FIG. 2a is a schematic cross-sectional plan view of an anchoring member.

FIG. 2b is a top plan schematic view of the proximal end of theanchoring member.

FIG. 3 is a schematic perspective view of an anchoring member with thelocking member.

FIG. 4 is a schematic cross-sectional plan view of an anchoring memberwith the locking member

FIG. 5 is a perspective view of an anchoring member holding an object(plate).

FIG. 6a is a cross-sectional view of the shaft (Hex Key) of oneembodiment of the first fastener F1.

FIG. 6b is a schematic perspective view of the distal end (ball end hextool) of the first fastener F1.

FIG. 6c is a lateral view of the first fastener F1.

FIG. 7 is a schematic perspective view of a differential that can beused for the second fastener F2.

FIG. 8a is an enlarged perspective view of the distal end (ball end hextool) of the first fastener F1.

FIG. 8b is an enlarged lateral view of the distal end (ball end hextool) showing a 25 to 30 degree angle entry to the hex tool.

FIG. 8c is an example of oblique insertion.

FIG. 8d is a lateral view of the first fastener F1 engaged within a hexscrew.

FIG. 9a is a lateral view of a cortical-type locking member L.

FIG. 9b is a lateral view of a cancelous-type locking member L.

FIG. 9c is a lateral view of a headless-type locking member L.

FIGS. 10A-C illustrates various angulation patterns of the interlockinganchor and locking members.

FIG. 11 illustrates one embodiment of a locking member within ananchoring member, in addition to the respective fastener having acorresponding angulation to the angulation of the locking member withinthe anchoring member.

FIG. 12 illustrates an exemplary embodiment of a fastener and itscorresponding locking member within the anchoring member.

FIGS. 13A-13I illustrates exemplary embodiments of the shape of thesocket for insertion of the respective fastener in the anchor or lockingmember.

From the foregoing disclosure and the following more detaileddescription of various particular embodiments it will be apparent tothose skilled in the art that the present invention provides asignificant advance in the art of bone anchoring devices. Additionalfeatures and advantages of various particular embodiments will be betterunderstood in view of the detailed description provided below.

DETAILED DESCRIPTION OF THE INVENTION

The present invention incorporates by reference herein in its entiretyU.S. Provisional Patent Application Ser. No. 60/896,960, filed Mar. 26,2007.

The term “a” or “an” as used herein in the specification may mean one ormore. As used herein in the claim(s), when used in conjunction with theword “comprising”, the words “a” or “an” may mean one or more than one.As used herein “another” may mean at least a second or more. Someembodiments of the invention may consist of or consist essentially ofone or more elements, method steps, methods and/or systems of theinvention. It is contemplated that any system, method, or compositiondescribed herein can be implemented with respect to any other method orcomposition described herein.

I. The Present Invention

It will be apparent to those skilled in the art, that is, to those whohave knowledge or experience in this area of technology, that manyvariations are possible for the system for anchoring bone disclosedherein. The following detailed discussion of various and particularfeatures and embodiments will illustrate the general principles of theinvention with reference to an improved bone anchoring device for use inmammalian bone, including vertebrae, for example. Other embodimentssuitable for other applications will be apparent to those skilled in theart given the benefit of this disclosure.

Any mammalian bone, including human bone, may have the inventivesystems, methods, and/or compositions of the present invention appliedthereto. Examples include long, short, flat, irregular, accessory, andsesamoid bones. Particular examples include but are not limited tovertebrae, femur, humerus, radius, ulna, femur, tibia, fibula, clavicle,rib, metacarpals, metatarsals, phalanges, skull bones, sternum,scapulae, innominates, vertebrae, maxillae, sphenoid, carpus, tarsus,patella, interfrontal bone, epipteric bone, coronal ossicle, bregmaticossicle, sagittal ossicle, lambdoid ossicle, and squame-parietalossicle.

The materials of the components of the present invention may be of anysuitable kind. Materials of the anchor and locking member arebiocompatible, in certain embodiments. Examples of materials includebiomedical metallic materials, including stainless steel; alloys (Al,Co, Ni, Ta, W, V, etc.); cobalt-based alloys; or titanium and itsalloys. Other examples of materials include polymeric biomaterials, suchas synthetic non-biodegradable polymers: polyethylene (high densitypolyethylene—HDPE—, ultrahigh molecular weight polyethylene—UHMWPE—),poly (ether ether ketone) or PEEK. Polymer matrix composite biomaterialsmay be employed and include fiber-reinforced composites (for example,carbon fiber or kevelar).

The shape, diameter, length, and any associated angles of the anchor,locking member, and, by extrapolation, fastener(s) of the inventionmaybe of any kind, so long as the locking member is able to bepositioned within the anchor at an angle to generate a V-shaped (orL-shaped, in a 90 degree configuration) configuration and so long as thecorresponding fastener(s) can be inserted in the respective socket 104in the head of anchor and/or locking member to apply torque for affixingthem into bone.

Referring now to FIGS. 1 to 9, in accordance with an illustrativeembodiment of the present invention, an anchoring device or implant,generally referred to using the numeral 100, will now be described. Theanchoring system 100 is generally comprised of an anchoring member A anda locking member L (see FIG. 3).

FIG. 1 illustrates an anchoring member A in accordance with a certainembodiment. The anchoring member A generally has cancelous screws'features such as a 2-portion shaft comprising an optionally coarse,self-tapping thread 103, designed to anchor in the softer medullary orcancelous bone, and topped by a smooth unthreaded portion 101 thatallows it to act as a lag screw. The unthreaded upper portion 101presents an oblique aperture 102 having an angle (for example, of about25°) with respect to an axial plane of the anchoring member's shaft. Theproximal end of the anchoring member A has a proximal end socket 104such that it can be engaged by a fastener like a key, screwdriver, orwrench (see FIG. 2b ). In specific embodiments, the proximal end of theanchoring member A has a Hex (hexagonal) type's proximal end socket 104such that it can be engaged by a Hex tip fastener like a key or wrench(see FIG. 2b ).

The term “fastener” as used herein refers to a tool, such as a wrench,key, or screwdriver, that is employed to insert the corresponding anchorin the bone via the head of the anchor and/or to insert thecorresponding locking member in the anchor via the socket 104 of thehead of the locking member.

Although the socket 104 of the head of the anchor or locking member maybe of any shape, the embodiment presented herein wherein both heads arehexagonal is merely illustrative. That is, the shape of the socket 104for insertion of the respective fastener in the anchor or locking membermay be of any shape, including hexagonal, pentagonal, square,triangular, cross-shaped, plus sign-shaped, linear, star-shaped, and soforth, for example. In a specific embodiment, the head of the lockingmember is smaller than the head of the anchor, although in otherembodiments the head of the locking member is the same size as the headof the anchor. In another specific embodiment, the socket 104 of theproximal end of the anchor and the socket 104 of the proximal end of thelocking member are identical in shape and/or size, whereas in otherspecific embodiments the socket 104 of the proximal end of the anchorand the socket 104 of the proximal end of the locking member are notidentical in shape and/or size.

FIG. 2 shows a cross-sectional view of the anchoring member (FIG. 2a )and a top plan of the proximal end of the anchoring member (FIG. 2b ).The shape of the socket 104 for insertion of the respective fastener inthe anchor or locking member may be of any shape, including hexagonal,pentagonal, square, triangular, cross-shaped, plus sign-shaped, linear,star-shaped, and so forth, for example (see FIG. 13A-13I); these may bereferred to as slotted, Phillips, Pozidriv, torx, Hex key, Robertson,Tri-Wing, Torq-Set, or Spanner, for example.

However, an exemplary hexagonal (Hex) socket in the head (104) of theanchoring member brings the following advantage: a ball end hex key (orwrench) can be used for angulated screwing and insertion, the contactsurfaces of the screw are protected from external damage, the tool canbe used with a headless screw, there are six contact surfaces betweenscrew and driver, the socket's depth are less prone to stripping, andthis room can be used for cannulation, for example.

FIG. 3 illustrates the anchoring system 100 comprising the anchoringmember A and the locking member L. The angle α between the two membersis fixed and set up at 25 degrees in a certain embodiment. This angleallows using a standard hex second fastener F2 (wherein F1 fastenerrefers to the fastener for the anchor and F2 fastener refers to thefastener for the locking member) equipped with an end ball hex end sinceit can be used with an angulation up to 30 degrees. In otherembodiments, the angle can be set up to another value comprised between1 to 90 degrees. In a specific embodiment, the angle can be 15-25degrees. Beyond 30 degrees angulation, another embodiment of the secondfastener F2 with an inclinable hex tip end may be used (differentialinner mechanism).

FIG. 4 is a schematic cross-sectional plan view of the anchoring system100. In this representation, a headless locking member L is engaged intoa oblique aperture (111) within the exemplary hex-shaped socket (104) ofthe head of the anchoring member A. The surface of the inner wall of theaperture may be threaded, smooth, or rough. One end of the aperture isat the proximal head of the anchor, and the opposite end is on one sideof the anchor.

FIG. 5 is a perspective view of an anchoring member holding an exemplaryobject (plate) P.

FIG. 6 illustrates the first fastener F1 with its Hex type tip (112). Inthis representation, the fastener comprises a head or tip that engageswith the socket of the anchor to apply torque by rotating the tip, suchas but not limited to a screwdriver, key or wrench. The tip is notlimited to hex type. The second fastener F2 in certain aspects comprisesa ball end hex type end to allow screwing of the locking member. Thesecond fastener F2 can have the same features as the first fastener F1when used in a particular embodiment e.g. with an angle α between thetwo members equal at 25 degrees, or inferior at 30 degrees at themaximum, in accordance with the working angle (25 to 30 degrees) of suchball end hex tip. In this case, only the size differs from the firstfastener F1, the second fastener F2 being thinner than the firstfastener F1 in order to be able to slid within the inner socket 104 ofthe first fastener F1, in particular embodiments.

In another embodiment an angle β, higher than the angle α, e.g. superiorat 30 degrees between the two members A and L, is set up. In thisembodiment, the second fastener F2 presents an inclinable tip able tomatch the angle β and is equipped with an inner mechanism applying thetorque in accordance with an oblique transmission of the rotating motionimparted to the handle of the fastener. Such mechanism can be but is notlimited to a differential, a screw gear, or a set of gears. FIG. 7illustrates the principle of such mechanism and shows a schematicconceptual view of a differential. Such a fastener can be rotatedmanually or by an electric or other motor.

Whatever the mechanism can be, it is intended to allow an obliquescrewing while the handle of the fastener remains straight forward, incertain embodiments. Such a feature is useful when the local anatomicalrequirements forbid the tool to be tilted. For example, when a surgeryusing a minimally invasive approach through a small incision isperformed, the instruments must go through this small cutaneousaperture, and therefore can not be angulated in order to avoid damagingsoft tissue.

FIG. 8a is an enlarged perspective view of the distal end (ball end hextool) of the fastener. The concept by which ball ends slide into a screwhead is known as funnel insertion. Basically, it means that the sides ofthe ball end direct (funnel) it into place. This allows fast funnelentry, eliminates wasted time even in blind applications, and the fulldepth engagement reduces “stripping” problems.

FIG. 8b is an enlarged lateral view of the distal end (ball end hextool) showing a 25 to 30 degree angle entry to hex. As maximum allowableangle increases, neck size decreases, and strength also decreases. Bycontrast, increasing the strength of a ball-end tool requires acorresponding increase in neck size and decrease in maximum allowableangle. Designing the perfect ball-end tool means choosing the idealbalance between strength and allowable angle. FIG. 8c is an example ofoblique insertion. FIG. 8d is a lateral view of the first fastener F1engaged within a hex screw.

FIG. 9 illustrates the three possible designs of the locking member L.In certain embodiments, the locking member L is thinner than theanchoring member A so that it can be slid through the oblique apertureand positioned within the empty room of the hexagonal socket of theanchoring member. Its length can be smaller, equal or bigger than theanchoring member. Its proximal end can be equipped with a head (105) orbe wide-mouthed (106) to block within the anchoring member's head, or beheadless (107). Whatever the type of the locking member L can be (headed105, wide-mouthed 106 or headless 107), the socket has a hex type shape,in certain embodiments. The locking member can be a cortical type screw(FIG. 9a ) with a fine thread (108) all along its shaft and thereforescrewed into an oblique threaded canal within the anchoring member'shead, or a cancelous type screw (FIG. 9b ) with a coarser thread (109),designed to anchor the bone and a smooth, unthreaded portion (110),designed to slid within an oblique unthreaded canal within the anchoringmember's head. Depending of its type, the locking member L can just actas an anti-rotational device and prevent the unscrewing of the anchoringmember A in the cortical type design, or be both a blocking system asdescribed above and an additional fastening device intended to secureand reinforce the grip within the medullary bone in the cancelous typedesign. Moreover, due to its divergent positioning, it brings to theconstruct a V-shaped design which opposes to pull-out forces. Whatevercancelous or cortical type design be used, the adjunction of a seconddivergent member (locking member L) advantageously increases both thegrip and the purchase within the bone, especially in cancelous and/orosteoporotic bone and therefore opposes to pull-out and secures thefixation of any object to the bone.

FIG. 10 illustrates various angulation patterns of the interlockinganchor and locking members. Upon certain angulations of the lockingmember within the anchoring member, and therefore, certain angulationsrequired for the corresponding fastener to screw the locking member, theproximal end of the anchoring member requires a cavity at its socket toallow the fastener access to the locking member.

FIG. 11 illustrates one embodiment of a locking member within ananchoring member, in addition to the respective fastener having acorresponding angulation to the angulation of the locking member withinthe anchoring member. In this specific embodiment, the proximal end ofthe anchoring member has a cavity that allows insertion of the fastenerfor the locking member.

FIG. 12 illustrates an exemplary embodiment of a fastener and itscorresponding locking member within the anchoring member. The proximalend of the anchoring member comprises a cavity that allows insertion ofthe fastener for the locking member.

In certain embodiments, the anchor and locking member are coated withantibiotic or other medicine useful upon implantation of an implant onand/or in a bone. In other embodiments, the surface of the anchor and/orlocking member is rough for a better grip within the bone.

Any of the compositions described herein may be comprised in a kit.Where there are more than one components in the kit, the kit also maycontain a second, third or other additional container into which theadditional components may be separately placed. The kits of the presentinvention may include a means for containing the invention component(s)in close confinement for commercial sale. Such containers may includeinjection or blow molded plastic containers into which the componentsare retained, for example.

The kit may comprise the anchor, locking member, and/or fastener(s). Insome cases, all components are sold separate, whereas in other cases allor a subset of components are sold together. Irrespective of the numberand/or type of containers, the kits of the invention may also comprise,and/or be packaged with, an instrument other than a fastener(s) of theinvention for assisting with placing the anchor/locking member withinthe body of an animal.

In particular embodiments of the invention, a variety of anchors,locking members, and/or fasteners may be provided in a kit. For example,a variety of lengths, diameters, socket shapes, and/or angles of thecorresponding anchors, locking members, and/or fastener(s) may beprovided in a kit.

From the foregoing disclosure and detailed description of certainembodiments, it will be apparent that various modifications, additionsand other alternative embodiments are possible without departing fromthe true scope and spirit of the invention. The embodiments discussedwere chosen and described to provide the best illustration of theprinciples of the invention and its practical application to therebyenable one of ordinary skill in the art to use the invention in variousembodiments and with various modifications as are suited to theparticular use contemplated. All such modifications and variations arewithin the scope of the invention as determined by the appended claimswhen interpreted in accordance with the breadth to which they arefairly, legally, and equitably entitled.

What is claimed is:
 1. A method for securing an anchoring member to bonetissue, the method comprising the steps of: driving the anchoring memberinto a first location of the bone tissue along a central axis that isoriented along a longitudinal direction, the anchoring member includinga proximal end that defines a proximal surface and a distal end that isspaced from the proximal end along the central axis; after the drivingstep, positioning a distal end of a locking member into a socket definedby the proximal end of the anchoring member such that the distal end ofthe locking member is aligned with an aperture partially defined by thesocket, wherein an entirety of the aperture is spaced from an entiretyof the proximal surface with respect to the longitudinal direction;advancing the distal end of the locking member through the aperturealong a central aperture axis that is oblique with respect to thecentral axis and the proximal surface, such that the distal end of thelocking member is driven into a second location of the bone tissue and aproximal end of the locking member is recessed within the anchoringmember from the proximal surface of the anchoring member, wherein theproximal end of the locking member is opposite the distal end of thelocking member; and threadedly engaging a threaded shaft of the lockingmember with the second location of the bone tissue.
 2. The method ofclaim 1, wherein the advancing step includes advancing the lockingmember along the central aperture axis until the proximal end of thelocking member is seated in the aperture.
 3. The method of claim 1,wherein the driving step includes threadably engaging a threaded shaftof the anchoring member to the first location of the bone tissue.
 4. Themethod of claim 1, wherein the proximal end of the anchoring memberdefines an inner aperture wall that, in turn, defines the aperture,wherein the advancing step includes threadably advancing the threadedshaft of the locking member along a threaded portion of the inneraperture wall.
 5. The method of claim 1, wherein the driving stepincludes: coupling a tool to the socket; and applying, via the tool, atorsional force to the anchoring member so as to drive the anchoringmember into the first location of the bone tissue.
 6. The method ofclaim 5, wherein the tool is configured to engage the socket of theanchoring member and a socket of the locking member, wherein theadvancing step includes: coupling the tool to the socket of the lockingmember; and applying, via the tool, a torsional force to the lockingmember so as to drive the anchoring member into the first location ofthe bone tissue.
 7. The method of claim 5, wherein the tool is a firsttool, the advancing step includes: coupling a second tool to a socket ofthe locking member; and applying, via the second tool, a torsional forceto the locking member so as to drive the locking member into the secondlocation of the bone tissue.
 8. The method of claim 1, wherein a socketopening is aligned with the proximal surface such that the socketextends from the proximal surface along the longitudinal directiontoward the distal end of the anchor member, wherein the positioning stepincludes positioning the distal end of the locking member through thesocket opening and into the aperture.
 9. The method of claim 1, whereinthe central aperture axis extends through the socket, and thepositioning step includes positioning the distal end of the lockingmember through the socket along the central aperture axis and into theaperture.
 10. The method of claim 1, wherein the anchoring member is afirst anchoring member, the socket is a first socket, the aperture is afirst aperture, the central axis is a first central axis, and thelocking member is a first locking member, where the method includes thesteps of: driving a second anchoring member into the bone tissue along asecond central axis that is oriented along a second direction;positioning a distal end of the second locking member into a secondsocket defined by the proximal end of the second anchoring member suchthat the distal end of the second locking member is aligned with thesecond aperture disposed in the second socket; and advancing the secondlocking member into the second aperture such that the distal end of thesecond locking member is driven into the bone tissue.
 11. The method ofclaim 1, wherein the bone tissue is a long bone, and the driving stepincludes driving the anchoring member into first location of the longbone.
 12. The method of claim 1, further comprising, prior to thedriving step, the step of placing an object proximate to the bonetissue, wherein the driving step includes driving the anchoring memberinto the first location of the bone tissue so that the proximal end ofthe anchoring member holds the object with respect to the bone tissue.13. The method of claim 12, wherein the driving step includes drivingthe anchoring member into a hole in the object and into the firstlocation of the bone tissue.
 14. The method of claim 13, wherein theobject is a plate, and the placing step includes placing the plateproximate to the bone tissue, and the driving step includes driving theanchoring member into the hole of the plate and into first location ofthe bone tissue.